Concrete pier - so cheap & effective
Posted 03 September 2021 - 12:43 AM
While I am sure they are robust, I made my bombproof concrete pier for just over £100 in materials. It easily takes a C11 on an EQ6 without breaking a sweat.
That being said, now it is concreted into the ground, I cannot take mine with me if and when we move house. This is the true benefit of a metal pier. When we do move, I shall simply pour a new one, wherever that may be.
Measurements are 1.2m tall x 0.3x0.3m square with M20 bolts supporting the top plate. It took a day to prep the shed and make the wooden framing (with hindsight, I should have bought a length of scrap air conditioning duct) and a morning to pour the cement.
Thank goodness my friend, Ian, who has an observatory in Bath was able to bring his mixer and lead the show as I have never mixed concrete before. Thanks, Ian.
The first few buckets were wet and, with a rebar cage, ensured a good bond to the concrete floor. It isn’t going anywhere!
The bolts for the top plate were put in the cement while it was cured but I added further bonding with the rawl-plug epoxy (whatever it is called!) as belts and braces.
After a week of curing, it is now loaded up waiting for clear skies. Hurrah!
Full build - including using cup of tea to check the level is here: https://youtu.be/zUSMDIDESlQ
- elpajare, OldManSky and DSOGabe like this
Posted 03 September 2021 - 08:36 AM
I don't know how to weld, so I also am thankful for concrete. I was also able to easily put conduit in my pier so my cables run under my observatory floor and through my pier. No cables on the floor.
You guys did a good job minimizing honeycomb (those "holes" in the side of the concrete). I was going to suggest using mortar to point the holes, but I saw later you'd filled them with resin.
Edited by macdonjh, 03 September 2021 - 08:43 AM.
Posted 03 September 2021 - 06:37 PM
"...including using cup of tea to check the level..."
And nicely done!
My concrete pier was significantly less costly than £100. $32 in concrete, $6 in rebar, $8 for sonotube.
If I move (doubtful!), I'll pour another.